In general, a mobile communication system requires managing an accurate position of a subscriber in order to provide a smooth communication service to the subscriber.
For the smooth communication service, when a User Equipment (UE) first accesses the network, an authentication of the corresponding UE is performed, and the UE having normally passed authentication is registered in the network. Further, the mobile communication system performs system management to support mobility of the corresponding UE by setting a session and a bearer of the UE registered in the network.
The management to support the mobility representatively includes system management of position information of the corresponding UE. In order to manage the position of the UE, the system management is required to be periodically informed of the position information from the UE.
FIG. 1 illustrates an example of a conventional mobile communication system for registering a position of a UE according to the related art. The mobile communication system illustrated in FIG. 1 operates based on the Long Term Evolution (LTE) corresponding to the fourth generation communication network.
Referring to FIG. 1, a UE 10 is located within a service area 40 of Base Station (BS) A 30. The UE 10 accesses (is attached to) an LTE network 70 through BS A 30. The UE 10 periodically reports its own position information in response to a request by a position information management server that manages position information of a user. For example, the position information management server includes an LTE Positioning Protocol (LPP) server 20.
The UE 10 can move from the service area 40 of BS A30 to a service area 60 of another BS, that is, BS B 50. In general, a condition where signal transmission/reception is not normally performed as the UE escapes from a service area of a serving BS in the LTE network is referred to as “Out of LTE Service Area”. Referring to FIG. 1, the UE having moved to the service area 60 of BS B 50 is illustrated as a “UE′ 10′”.
The UE′ 10′ cannot report its own position information to the LPP server 20 through BS A 30 anymore. In this case, the UE′ 10′ re-accesses (is re-attached to) the LTE network 70 through BS B 50. After re-accessing (being re-attached to) the LTE network 70, the UE′ 10′ reports its own position information to the LPP server 20 through a path according to the re-access (re-attachment) in response to a request by the LPP server 20.
In general, a method of reporting the position information of the user in a mobile communication system may be divided into two methods according to whether a response message is provided. That is, the two methods include a method (Over User Plane) in which the position information management server does not provide a response message corresponding to the position information reported by the UE and a method (Over Control Plane) in which the position information management server provides a response message.
FIG. 2 illustrates an example of a signal processing procedure of reporting user position information based on the method in which the response message is not provided in the mobile communication system based on the general LTE network according to the related art.
It is assumed that the UE 10 includes a measurement module 12, an LPP module 14, and a Non-Access Stratum (NAS) module 16 as illustrated in FIG. 4 for the signal processing procedure in FIG. 2. The management module 12 includes A-GNSS 19, OTDOA 17 and ECID 18. Since the signal processing procedure in FIG. 2 corresponds to the method in which the response message is not provided, the UE 10 does not need to include an acknowledgement block 15 of FIG. 4.
Further, it is assumed that the LPP server 20 includes an Enhanced Serving Mobile Location Center (E-SMLC)/SUPL Location Platform (SLP) module 22 that manages position information of the user.
For example, the signal processing procedure of FIG. 2 may be performed when a request for the response message is not set within the message reported by the UE 10. That is, the LPP server 20 does not transmit the response message in response to the received message when the acknowledgement is not set within the message through which the UE 10 reports the position information.
Referring to FIG. 2, the UE 10 receives position information report request (Request Location Information) from the LPP server 20, and reports its own position information (LPP Location Information) based on a Report Interval (RI) set within a predetermined reporting amount in response to the position information report request (Request Location Information). That is, the UE 10 receives the position information report request (Request Location Information) in operation 210, and reports the position information (LPP Location Information) in operations 250, 252, 254, 256, 258, 260, 260 and 264.
The predetermined reporting amount and the Report Interval (RI) on which the position information is reported within the predetermined reporting amount may be set by information provided when the position information report request (Request Location Information) from the LPP server 20 is made.
All position information (LPP Location Information) reported by the UE 10 may not be provided to the LPP server 20. That is, the position information (LPP Location Information) reported in a state where the UE 10 cannot normally use the mobile communication service, that is, a state of “Out of LTE Service 290” is not received by the LPP server 20 in operations 258, 260, 262 and 264.
Meanwhile, in order to allow the UE 10 to report the position information to the LPP server 20, the modules included in the UE 10 generate a message through which the position information is reported, and perform an operation to transmit the generated message.
For example, the measurement (A-GNSS/OTDOA/ECID) module 12 generates a message through which its own position information measured based on the RI set within the predetermined reporting amount is reported in operations 214 to 228. The LPP module 14 transmits the message generated by the measurement (A-GNSS/OTDOA/ECID) module 12 to the NAS module 16 in response to the position information report request (Request Location Information) provided from the NAS module 16 in operations 212, 230, 232, 234, 236, 238, 240, 242 and 244.
The NAS module 16 transmits the report message provided from the LPP module 14 to the E-SMLC/SLP module 22 in operations 250, 252, 254, 256, 258, 260, 262 and 264.
However, the message reported by the NAS module 16 in the state of “Out of LTE Service 290” in operations 258, 260, 262 and 264 cannot be normally transmitted to the E-SMLC/SLP module 22 of the LPP server 20.
The NAS module 16 cannot identify whether the report message transmitted in the state of “Out of LTE Service 290” has been normally transmitted to the E-SMLC/SLP module 22 of the LPP server 20.
Accordingly, the modules within the UE 10 cannot help generating the message through which the position information is reported and continuously performing an operation to transmit the generated message to the LPP server 20 even in the state of “Out of LTE Service 290”.
As described above, since the signal processing procedure illustrated in FIG. 2 does not have a reference which can determine the stop (abort) of the position information report by itself, an unnecessary processing load in the state of “Out of LTE Service” may be generated. Further, due to the state of “LTE Out of Service”, the fact that “Out of LTE Service” has been generated cannot be provided from the LPP server. In addition, since the SUPL in charge of LPP related session connection and maintenance is not a component within a modem, the SUPL may not receive a position report stop command.
FIG. 3 illustrates an example of the signal processing procedure of reporting user position information based on the method in which the response message is provided in the mobile communication system based on the general LTE network according to the related art.
It is assumed that the UE 10 includes the measurement (A-GNSS/OTDOA/ECID) module 12, the LPP module 14, and the NAS module 16 as illustrated in FIG. 4 for the signal processing procedure in FIG. 3. For the signal processing procedure of FIG. 3, the UE 10 is required to further include the acknowledgement block 15.
Further, it is assumed that the LPP server 20 includes the Enhanced Serving Mobile Location Center (E-SMLC)/SUPL Location Platform (SLP) module 22 that manages position information of the user.
For example, the signal processing procedure of FIG. 3 may be performed when a request for the response message is set within the message reported by the UE 10. That is, the LPP server 20 transmits the response message in response to the received message when the acknowledgement is set within the message through which the UE 10 reports the position information. For example, in LPP Over Control plane, an Acknowledgement Request may be inserted into the LPP message through which the position information is reported and then the LPP message may be transmitted.
Referring to FIG. 3, the UE 10 receives position information report request (Request Location Information) from the LPP server 20, and reports its own position information (LPP Location Information) based on the RI set within the predetermined reporting amount in response to the position information report request (Request Location Information). That is, the UE 10 receives the position information report request (Request Location Information) in operation 310, and reports the position information (LPP Location Information) in operations 350, 352, 354 and 356.
The LPP server 20 transmits a response message (LPP Acknowledgement) to the UE 10 in response to each of the position information reported by the UE 10 in operations 370, 372 and 374. The UE 10 receives the response message (LPP Acknowledgement) transmitted from the LPP server 20 and thus recognizes that the position information reported by itself has been normally received by the LPP server 20.
The predetermined reporting amount and the Report Interval (RI) on which the position information is reported within the predetermined reporting amount may be set by information provided when the position information report request (Request Location Information) from the LPP server 20 is made.
All position information (LPP Location Information) reported by the UE 10 may not be provided to the LPP server 20. That is, the position information (LPP Location Information) reported in a state where the UE 10 cannot normally use the mobile communication service, that is, a state of “Out of LTE Service 390” is not received by the LPP server 20 in operations 358, 360 and 362.
In this case, the UE 10 cannot receive the response message in response to the position information reported in operations 358, 360 and 362 from the LPP server 20.
Meanwhile, in order to allow the UE 10 to report the position information to the LPP server 20, the modules included in the UE 10 generate a message through which the position information is reported, and perform an operation to transmit the generated message.
For example, the measurement (A-GNSS/OTDOA/ECID) module 12 generates a message through which its own position information measured based on the RI set within the predetermined reporting amount is reported in operations 314, 316, 318, 320 and 322. However, the measurement (A-GNSS/OTDOA/ECID) module 12 stops generating the message for reporting the position information when the measurement (A-GNSS/OTDOA/ECID) module 12 does not receive the response message from the E-SMLC/SLP module 22 of the LPP server 20.
The LPP module 14 transmits the message generated by the measurement (A-GNSS/OTDOA/ECID) module 12 to the NAS module 16 in response to the position information report request (Request Location Information) provided from the NAS module 16 in operations 330, 332, 334, 336, and 337 to 339.
The LPP module 14 receives the response message received from the E-SMLC/SLP module 22 of the LPP server 20 from the NAS module 16 in response to the report message which has been transmitted to the NAS module 16 in operations 340, 342 and 344.
The LPP module 14 stops transmitting the report message to the NAS module 16 when the LPP module 14 does not receive the response message from the E-SMLC/SLP module 22 of the LPP server 20.
The NAS module 16 transmits the report message provided from the LPP module 14 to the E-SMLC/SLP module 22 in operations 350, 352, 354, and 356. Further, the NAS module 16 receives the response message from the E-SMLC/SLP module 22 of the LPP server 20 in response to the position information reported to the E-SMLC/SLP module 22 of the LPP server 20 in operations 370, 372 and 374.
However, when the NAS module 16 does not receive the response message from the E-SMLC/SLP module 22 of the LPP server 20 due to a state of “Out of LTE Service 390”, the LPP module 14 transmits the position information to the NAS module 16 by a predetermined number of times (for example, three times) on a preset period (Ack timeout period, a maximum of 250 ms) in operations 337 to 339. At this time, the transmitted position information may be information of a position where the response message is not received.
Accordingly, when the LPP module 14 does not receive the response message from the NAS module 16 or the E-SMLC/SLP module 22 of the LPP server 20, the LLP module 14 transmits the position information by the preset number of times (for example, three times).
Meanwhile, when the LPP module 14 and the NAS module 16 do not receive the response message even though they have re-transmitted the position information by the preset number of times, the LPP module 14 and the NAS module 16 stop all operations related to the transmission of the position information.
As described above, the signal processing procedure illustrated in FIG. 3 determines a reference to stop transmitting the report message as “a case where the response message is not received”. However, the LPP including the UE requires reducing unnecessary LPP processing steps regardless of the user plane or the control plane.
In connection with this, the conventional mobile communication system does not disclose an operation for restarting transmission of the report message, which has stopped due to the non-reception of the response message. Accordingly, it is required to provide an efficient method of restarting the stopped transmission of the report message in the mobile communication system.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.